Enter the product key for your Office 2007 program
When you install your Office 2007 program, you are prompted to type or paste in the 25-character Product Key.
Although you are not required to enter your Product Key at installation, we recommend you do so because it helps to verify that your software is legitimate. You may run your Office 2007 programs up to 25 times before you are required to enter a Product Key. After this grace period, if you have not entered a valid Product Key, the software goes into Reduced Functionality mode and many features are unavailable.
The Product Key for a Full product may be located or requested in one of the following locations:
Sticker on the CD case or other packaging.
Certificate of Authenticity.
Confirmation email message received from an online purchase.
Do not lose your Product Key. Keep the packaging, or write the number down and keep it in a safe place. If you lose your Product Key and have a valid proof of purchase, contact Microsoft support for help.